Download Solar PV Standard Plan - Simplified Central/String Inverter Systems

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Solar PV Standard Plan — Simplified
Central/String Inverter Systems for
One- and Two-Family Dwellings
SCOPE: Use this plan ONLY for utility-interactive central/string inverter systems not exceeding a system AC inverter output rating of
10kW on the roof of a one- or two-family dwelling or accessory structure. The photovoltaic system must interconnect to the load side of
a single-phase AC service panel of nominal 120/240Vac with a bus bar rating of 225A or less. This plan is not intended for bipolar
systems, hybrid systems or systems that utilize storage batteries, charge controllers, trackers, more than two inverters or more than one
DC combiner (noninverter-integrated) per inverter. Systems must be in compliance with current California Building Standards Codes and
local amendments of the authority having jurisdiction (AHJ). Other Articles of the California Electrical Code (CEC) shall apply as specified
in 690.3.
MANUFACTURER’S SPECIFICATION SHEETS MUST BE PROVIDED for proposed inverter, modules, combiner/junction boxes and racking
systems. Installation instructions for bonding and grounding equipment shall be provided, and local AHJs may require additional
details. Listed and labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling
(CEC 110.3). Equipment intended for use with PV system shall be identified and listed for the application (CEC 690.4[D]).
Job Address: ______________________________________________ Permit #: ________________________
Contractor/Engineer Name: _________________________________ License # and Class: _______________
Signature: _______________________________ Date: ___________ Phone Number: __________________
Total # of Inverters installed: __________ (If more than one inverter, complete and attach the “Supplemental
Calculation Sheets” and the “Load Center Calculations” if a new load center is to be used.)
Inverter 1 AC Output Power Rating: _______________________ Watts
Inverter 2 AC Output Power Rating (if applicable): ____________Watts
Combined Inverter Output Power Rating: ___________________≤ 10,000 Watts
Location Ambient Temperatures (Check box next to which lowest expected temperature is used):
1)
Lowest expected ambient temperature for the location (TL ) = Between -1° to -5° C
Lowest expected ambient temperature for the location (TL ) = Between -6° to -10° C
Average ambient high temperature (TH) = 47° C
Note: For a lower TL or a higher TH, use the Comprehensive Standard Plan
DC Information:
Module Manufacturer: __________________________
Model: ______________________________
2) Module Voc (from module nameplate): ______ Volts 3) Module Isc (from module nameplate): ______ Amps
4) Module DC output power under standard test conditions (STC) = ________ Watts (STC)
5) DC Module Layout
Identify each source circuit
(string) for inverter 1 shown
on the roof plan with a Tag
(e.g. A,B,C,…)
Number of modules per
source circuit for inverter 1
Identify, by tag, which source circuits on the roof are to be
paralleled (if none, put N/A)
Combiner 1:
Combiner 2:
Total number of source circuits for inverter 1:
6) Are DC/DC Converters used?
Yes
No
If No, skip to Step 7. If Yes enter info below.
DC/DC Converter Model #: __________________
DC/DC Converter Max DC Input Voltage: ______ Volts
Max DC Output Current: ____________________ Amps
Max DC Output Current: ___________________ Volts
Max # of DC/DC Converters in an Input Circuit: ___________
DC/DC Converter Max DC Input Power: _______ Watts
7) Maximum System DC Voltage — Use A1 or A2 for systems without DC/DC converters, and B1 or B2 with DC/DC Converters.
A1. Module VOC (STEP 2) = ____________ x # in series (STEP 5) ___________ x 1.12 (If -1 ≤ TL ≤ -5°C, STEP 1) = ____________ V
A2. Module VOC (STEP 2) = ____________ x # in series (STEP 5) ___________ x 1.14 (If -6 ≤ TL ≤ -10°C, STEP 1) = ___________ V
Table 1. Maximum Number of PV Modules in Series Based on Module Rated VOC for 600 Vdc Rated Equipment (CEC 690.7)
Max. Rated Module VOC (*1.12)
29.76 31.51 33.48 35.71 38.27 41.21 44.64 48.70 53.57 59.52 66.96 76.53 89.29
(Volts)
Max. Rated Module VOC (*1.14)
29.24 30.96 32.89 35.09 37.59 40.49 43.86 47.85 52.63 58.48 65.79 75.19 87.72
(Volts)
Max # of Modules for 600 Vdc
18
17
16
15
14
13
12
11
10
9
8
7
6
Use for DC/DC converters. The value calculated below must be less than DC/DC converter max DC input voltage (STEP 6).
B1. Module VOC (STEP 2) = ________ x # of modules per converter (STEP 6) ______ x 1.12 (If -1 ≤ TL ≤ -5°C, STEP 1) = _______ V
B2. Module VOC (STEP 2) = ________ x # of modules per converter (STEP 6) ______ x 1.14 (If -6 ≤ TL ≤ -10°C, STEP 1) = ______ V
Table 2. Largest Module VOC for Single-Module DC/DC Converter Configurations (with 80 V AFCI Cap) (CEC 690.7 and 690.11)
Max. Rated Module VOC (*1.12)
30.4 33.0 35.7 38.4 41.1 43.8 46.4 49.1 51.8 54.5 57.1 59.8 62.5 65.2 67.9 70.5
(Volts)
Max. Rated Module VOC (*1.14)
29.8 32.5 35.1 37.7 40.4 43.0 45.6 48.2 50.9 53.5 56.1 58.8 61.4 64.0 66.7 69.3
(Volts)
DC/DC Converter Max DC Input
(Step #6) (Volts)
34
37
40
43
46
49
52
55
58
61
64
67
70
73
76
8) Maximum System DC Voltage from DC/DC Converters to Inverter — Only required if Yes in Step 6
Maximum System DC Voltage = _______________ Volts
9) Maximum Source Circuit Current
Is Module ISC below 9.6 Amps (Step 3)?
Yes
No (If No, use Comprehensive Standard Plan)
79
10) Sizing Source Circuit Conductors
Source Circuit Conductor Size = Min. #10 AWG copper conductor, 90° C wet (USE-2, PV Wire, XHHW-2,
THWN-2, RHW-2)
For up to 8 conductors in roof-mounted conduit exposed to sunlight at least ½” from the roof covering (CEC 310)
Note: For over 8 conductors in the conduit or mounting height of lower than ½” from the roof, use Comprehensive Plan.
11) Are PV source circuits combined prior to the inverter?
Yes
No
If No, use Single Line Diagram 1 and proceed to Step 13.
If Yes, use Single Line Diagram 2 with Single Line Diagram 4 and proceed to Step 12.
Yes
No
Is source circuit OCPD required?
Source circuit OCPD size (if needed): 15 Amps
12) Sizing PV Output Circuit Conductors — If a combiner box will NOT be used (Step 11),
Output Circuit Conductor Size = Min. #6 AWG copper conductor
13) Inverter DC Disconnect
Does the inverter have an integrated DC disconnect?
Yes
No If Yes, proceed to step 14.
If No, the external DC disconnect to be installed is rated for ______ Amps (DC) and ______ Volts (DC)
14) Inverter Information
Manufacturer: ______________________________
Model: _______________________________
Max. Continuous AC Output Current Rating: _______ Amps
Integrated DC Arc-Fault Circuit Protection?
Yes
No (If No is selected, Comprehensive Standard Plan)
Grounded or Ungrounded System?
Grounded
Ungrounded
AC Information:
15) Sizing Inverter Output Circuit Conductors and OCPD
Inverter Output OCPD rating = ______ Amps (Table 3)
Inverter Output Circuit Conductor Size = ______ AWG (Table 3)
Table 3. Minimum Inverter Output OCPD and Circuit Conductor Size
Inverter Continuous Output Current Rating (Amps) (Step 14)
12
16
20
24
28
32
36
40
48
Minimum OCPD Size (Amps)
15
20
25
30
35
40
45
50
60
Minimum Conductor Size (AWG, 75° C, Copper)
14
12
10
10
8
8
6
6
6
16) Point of Connection to Utility
Only load side connections are permitted with this plan. Otherwise, use Comprehensive Standard Plan.
Is the PV OCPD positioned at the opposite end from input feeder location or main OCPD location?
Yes
No
If Yes, circle the Max Combined PV System OCPD(s) at 120% value as determined from Step 15 (or Step
S20), bus bar Rating, and Main OCPD as shown in Table 4.
If No, circle the Max Combined PV System OCPD(s) at 100% value as determined from Step 15 (or Step
S20), bus bar Rating, and Main OCPD as shown in Table 4.
Per 705.12(D)(2): [Inverter output OCPD size [Step #15 or S20] + Main OCPD Size] ≤ [bus size x (100%
or 120%)]
Table 4. Maximum Combined Supply OCPDs Based on Bus Bar Rating (Amps) per CEC 705.12(D)(2)
Bus Bar Rating
100
125
125
200
200
200
225
225
225
Main OCPD
100
100
125
150
175
200
175
200
225
Max Combined PV System OCPD(s)
at 120% of Bus Bar Rating
20
50
25
60*
60*
40
60*
60*
45
Max Combined PV System OCPD(s)
at 100% Bus Bar Rating
0
25
0
50
25
0
50
25
0
*This value has been lowered to 60 A from the calculated value to reflect 10 kW AC size maximum.
Reduction of the main breaker is not permitted with this plan. Otherwise, use Comprehensive
Standard Plan.
17 & 18 & 19) Labels and Grounding and Bonding
This content is covered by the labels on the next page and the Single Line Diagram(s). For background
information, refer to the Comprehensive Standard Plan.
Solar PV Standard Plan — Simplified
Central/StringEXPEDITED
Inverter Systems
forPV
Oneand Two-Family
SOLAR
STANDARD
PLAN Dwellings
Central/String Inverter Systems for One and Two Family Dwellings
Markings
CEC Articles 690 and 705 and CRC Section R331 require the following labels or markings be installed at these
CEC
Articles 690
705 and CRC Section
components
of and
the photovoltaic
system:R331 require the following labels or markings be installed at these
components of the photovoltaic system:
WARNING
INVERTER OUTPUT CONNECTION;
DO NOT RELOCATE THIS
OVERCURRENT DEVICE
WARNING
DUAL POWER SOURCES
SECOND SOURCE IS PHOTOVOLTAIC SYSTEM
RATED AC OUTPUT CURRENT- ____AMPS AC
NORMAL OPERATING VOLTAGE ___VOLTS
M
CEC 705.12(D)(7)
[Not required if panelboard is rated not
less than sum of ampere ratings of all
overcurrent devices supplying it]
CEC 690.54 & CEC 705.12(D)(4)
WARNING
ELECTRIC SHOCK HAZARD. THE DC
CONDUCTORS OF THIS PHOTOVOLTAIC
SYSTEM ARE UNGROUNDED AND MAY
BE ENERGIZED
CEC 690.35(F)
[Only required for ungrounded systems]
PV SYSTEM AC DISCONNECT
RATED AC OUTPUT CURRENT - ____AMPS
AC NORMAL OPERATING VOLTAGE ___VOLTS
A
C
CEC 690.54
INVERTER
WARNING
ELECTRIC SHOCK HAZARD
IF A GROUND FAULT IS INDICATED,
NORMALLY GROUNDED CONDUCTORS
MAY BE UNGROUNDED AND ENERGIZED
CEC 690.5(C)
[Normally already present on listed inverters]
WARNING: PHOTOVOLTAIC
POWER SOURCE
WARNING
ELECTRIC SHOCK HAZARD
DO NOT TOUCH TERMINALS
TERMINALS ON BOTH LINE AND LOAD
SIDES MAY BE ENERGIZED IN THE
OPEN POSITION
CRC R331.2 and CFC 605.11.1
[Marked on junction/combiner boxes
and conduit every 10’]
J/Box
D
C
CEC 690.17
PV SYSTEM DC DISCONNECT
RATED MAX POWER-POINT CURRENT- ___ADC
RATED MAX POWER-POINT VOLTAGE- ___VDC
SHORT CIRCUIT CURRENT- ___ADC
MAXIMUM SYSTEM VOLTAGE- ___VDC
CEC 690.53
Code Abbreviations:
California Electrical Code (CEC)
California Residential Code (CRC)
California Fire Code (CFC)
Informational note: ANSI Z535.4 provides guidelines for the design of safety signs and labels for application to products. A phenolic
plaque with contrasting colors between the text and background would meet the intent of the code for permanency. No type size is
specified, but 20 point (3/8”) should be considered the minimum.
CEC 705.12 requires a permanent plaque or directory denoting all electric power sources on or in the premises.
3
Solar PV Standard Plan — Simplified
Central/String Inverter Systems for One- and Two-Family Dwellings
Solar PV Standard Plan — Simplified
Central/String Inverter Systems for One- and Two-Family Dwellings
Solar PV Standard Plan — Simplified
Central/String Inverter Systems for One- and Two-Family Dwellings
Supplemental Calculation Sheets for Inverter #2
(Only include if second inverter is used)
DC Information:
Module Manufacturer: __________________________
S2) Module Voc (from module nameplate): ______ Volts
Model: ______________________________
S3) Module Isc (from module nameplate): ______ Amps
S4) Module DC output power under standard test conditions (STC) = ________ Watts (STC)
S5) DC Module Layout
Identify each source circuit
(string) for inverter 1 shown
on the roof plan with a Tag
(e.g. A,B,C,…)
Number of modules per
source circuit for inverter 1
Identify, by tag, which source circuits on the roof are to be
paralleled (if none, put N/A)
Combiner 1:
Combiner 2:
Total number of source circuits for inverter 1:
S6) Are DC/DC Converters used?
Yes
No
If No, skip to Step S7. If Yes, enter info below.
DC/DC Converter Model #: __________________
DC/DC Converter Max DC Input Voltage: ______ Volts
Max DC Output Current: ____________________ Amps
Max DC Output Current: ___________________ Volts
Max # of DC/DC Converters in an Input Circuit: ___________
DC/DC Converter Max DC Input Power: _______ Watts
S7) Maximum System DC Voltage — Use A1 or A2 for systems without DC/DC converters, and B1 or B2 with DC/DC Converters.
A1. Module VOC (STEP S2) = ____________ x # in series (STEP S5) ___________ x 1.12 (If -1 ≤ TL ≤ -5°C, STEP S1) = ____________ V
A2. Module VOC (STEP S2) = ____________ x # in series (STEP S5) ___________ x 1.14 (If -6 ≤ TL ≤ -10°C, STEP S1) = ___________ V
Table 1. Maximum Number of PV Modules in Series Based on Module Rated VOC for 600 Vdc Rated Equipment (CEC 690.7)
Max. Rated Module VOC (*1.12)
29.76 31.51 33.48 35.71 38.27 41.21 44.64 48.70 53.57 59.52 66.96 76.53 89.29
(Volts)
Max. Rated Module VOC (*1.14)
29.24 30.96 32.89 35.09 37.59 40.49 43.86 47.85 52.63 58.48 65.79 75.19 87.72
(Volts)
Max # of Modules for 600 Vdc
18
17
16
15
14
13
12
11
10
9
8
7
6
Use for DC/DC converters. The value calculated below must be less than DC/DC converter max DC input voltage (STEP S6).
B1. Module VOC (STEP S2) = ________ x # of modules per converter (STEP S6) ______ x 1.12 (If -1 ≤ TL ≤ -5°C, STEP S1) = _______ V
B2. Module VOC (STEP S2) = ________ x # of modules per converter (STEP S6) ______ x 1.14 (If -6 ≤ TL ≤ -10°C, STEP S1) = ______ V
Table 2. Largest Module VOC for Single-Module DC/DC Converter Configurations (with 80 V AFCI Cap) (CEC 690.7 and 690.11)
Max. Rated Module VOC (*1.12)
30.4 33.0 35.7 38.4 41.1 43.8 46.4 49.1 51.8 54.5 57.1 59.8 62.5 65.2 67.9 70.5
(Volts)
Max. Rated Module VOC (*1.14)
29.8 32.5 35.1 37.7 40.4 43.0 45.6 48.2 50.9 53.5 56.1 58.8 61.4 64.0 66.7 69.3
(Volts)
DC/DC Converter Max DC Input
(Step 6) (Volts)
34
37
40
43
46
49
52
55
58
61
64
67
70
73
76
79
S8) Maximum System DC Voltage from DC/DC Converters to Inverter — Only required if Yes in Step S6
Maximum System DC Voltage = _______________ Volts
S9) Maximum Source Circuit Current
Is Module ISC below 9.6 Amps (Step S3)?
Yes
No (If No, use Comprehensive Standard Plan)
S10) Sizing Source Circuit Conductors
Source Circuit Conductor Size = Min. #10 AWG copper conductor, 90° C wet (USE-2, PV Wire, XHHW-2,
THWN-2, RHW-2)
For up to 8 conductors in roof-mounted conduit exposed to sunlight at least ½” from the roof covering (CEC 310)
Note: For over 8 conductors in the conduit or mounting height of lower than ½” from the roof, use Comprehensive
Plan.
S11) Are PV source circuits combined prior to the inverter?
Yes
No
If No, use Single Line Diagram 1 and proceed to Step S13.
If Yes, use Single Line Diagram 2 with Single Line Diagram 4 and proceed to Step S12.
Yes
No
Is source circuit OCPD required?
Source circuit OCPD size (if needed): 15 Amps
S12) Sizing PV Output Circuit Conductors — If a combiner box will NOT be used (Step S11),
Output Circuit Conductor Size = Min. #6 AWG copper conductor
S13) Inverter DC Disconnect
Does the inverter have an integrated DC disconnect?
Yes
No If Yes, proceed to Step S14.
If No, the external DC disconnect to be installed is rated for ______ Amps (DC) and ______ Volts (DC)
S14) Inverter Information
Manufacturer: ______________________________
Model: _______________________________
Max. Continuous AC Output Current Rating: _______ Amps
Integrated DC Arc-Fault Circuit Protection?
Yes
No (If No is selected, Comprehensive Standard Plan)
Grounded or Ungrounded System?
Grounded
Ungrounded
AC Information:
S15) Sizing Inverter Output Circuit Conductors and OCPD
Inverter Output OCPD rating = ______ Amps (Table 3)
Inverter Output Circuit Conductor Size = ______ AWG (Table 3)
Table 3. Minimum Inverter Output OCPD and Circuit Conductor Size
Inverter Continuous Output Current Rating (Amps) (Step 14)
12
16
20
24
28
32
36
40
48
Minimum OCPD Size (Amps)
15
20
25
30
35
40
45
50
60
Minimum Conductor Size (AWG, 75° C, Copper)
14
12
10
10
8
8
6
6
6
Load Center Calculations
(Omit if a load center will not be installed for PV OCPDs)
S20) Load Center Output:
Calculate the sum of the maximum AC outputs from each inverter.
Inverter #1 Max Continuous AC Output Current Rating [STEP S14] _______ × 1.25 = _______ Amps
Inverter #2 Max Continuous AC Output Current Rating [STEP S14] _______ × 1.25 = _______ Amps
Total inverter currents connected to load center (sum of above)
= _______ Amps
Conductor Size: ______ AWG
Overcurrent Protection Device: ______ Amps
Load center bus bar rating: ______ Amps
The sum of the ampere ratings of overcurrent devices in circuits supplying power to a bus bar or conductor
shall not exceed 120 percent of the rating of the bus bar or conductor.
Solar PV Standard Plan — Simplified
Central/String Inverter Systems for One- and Two-Family Dwellings
Solar PV Standard Plan — Simplified
Central/String Inverter Systems for One- and Two-Family Dwellings
Items required: roof layout of all panels, modules, clear access
pathways and approximate locations of electrical disconnecting
means and roof access points.
Roof Layout Diagram for One- and Two-Family Dwellings
SOLAR PV STANDARD PLAN